Obsidian
Types: Obsidian can come in a wide range of colors including black, dark green, brown, rainbow and "Snowflake" obsidian
Element: Fire
Deities: Baron Samedi, Oya, Pele, Freya, Wodin
Spiritual Use: Absorbing negativity, Grounding, Protection
Obsidian is volcanic glass primarily made up of silicon dioxide. The colors and types of obsidian will depended on the conditions of it's formation and the impurities present. Because it is created by lava flows, obsidian has a natural affinity for volcano deities like Madam Pele.
Obsidian was used by many cultures to make arrow heads, knife blades and other really sharp implements of destruction. This where obsidian gets it's reputation for protection. For this purpose, use an obsidian arrowhead as part of your protection spell.
I like to keep a big hunk of raw black obsidian around to absorb negativity. If you are attempting to do some emotional clearing, you will find obsidian can help you release that emotionally negativity. Obsidian is so good at absorb negative energy, please remember to smudge it with sage or cleanse it periodically or eventually it will break.
The green and brown varieties of obsidian are wonderful for grounding. If you find yourself scatter-brained or nervous, sit down and meditate with a piece either green or brown obsidian. It can help you find your center again.